diff --git a/src/main/scala/scalatutorial/sections/DefinitionsAndEvaluation.scala b/src/main/scala/scalatutorial/sections/DefinitionsAndEvaluation.scala
index 3aad0e95..d9599be5 100644
--- a/src/main/scala/scalatutorial/sections/DefinitionsAndEvaluation.scala
+++ b/src/main/scala/scalatutorial/sections/DefinitionsAndEvaluation.scala
@@ -220,7 +220,7 @@ object DefinitionsAndEvaluation extends ScalaTutorialSection {
     def triangleArea(base: Double, height: Double): Double =
       base * height / res0
 
-    triangleArea(3, 4) shouldBe 6
+    triangleArea(3, 4) shouldBe 6.0
     triangleArea(5, 6) shouldBe res1
   }